Valve-operating mechanism for internal-combustion engines.



v R. URTEL. VALVE OPERATING MECHANISM EUR INTERNAL COMBUSIION ENGINES.

APPLICATION FILED JAN. 7. I9II.

2 SHEETS-SHEET I.

Patented Oat. 12, 1915.

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VALVE OPERATING MECHANISM FOR INTERNAL COMBUSTION ENGINES.A APPucATloN man IAN. 7. 19u.

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y QudoWhUVteh MMI/MM,- y @MM RUDOLPH URTEL, AOF NIDERSCHONEWEIDE, GERMANY, ASSIG-NOR T0 GENERAL ELECTRIC COMPANY, A/CORPOBATION OF NEW YORK.

VALVE-OPERATING MECHANISM FR INTERNAL-COMBUSTIOII ENGINES.

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Specification of Letters Patent.

Patented Oct. 12, 1915..

Application led January 7, 1911. Serial No. 601,379.

To all 'whom 'it may concern.'

' Be it known that I, RUDOLPH URTEL, a subject of the King of Prussia, residing at Niederschoneweide, Germany, have invented certain new and useful Improvements in Valve-Uper'ating Mechanism for Internal- Combustion Engines, of which the following is a specication.

-This invention relates to internal combustion engines, of the type in which the admission and exhaust of the motive gases are controlled by a sleeve interposed between the piston and the walls of the cylinder, and arranged to reciprocate periodically to open and close certain ports. 4

The object of the present invention is to improve the mechanism by which said sleeve or tubular slide valve is operated.

In the accompanying drawings, Figure 1 is a longitudinal section of the cylinder, of an internal combustion engine equipped with a tubular slide valve and with one form of my improved valve-operating mechanism; Figs. 2, 3, 4 and 5 show modifications of Said operating mechanism; Fig. 6 is a diagram of the theoretical curve desired in the operation of the valve; Fig. 7 shows the curves of movement produced by two eccentrics running at vdifferent speeds; and Fig. 8 shows the curve resulting from a plotting of the variations of the two curves shown in Fig. 7.

As will be seen from Fig. l, the tubular slide valve 1 is interposed between the piston 2 and the walls ofthe cylinder 3, and is provided with two slots 4 and 5 near its upper end, one of which is located higher up than the other. These lslots are adapted to register at different times with the two slots 6 and 7 in the walls of the cylinder; said cylinder slots being at the same level and one constituting the inlet for the explosive mixture while the other serves as the exhaust for the burned gases. The tubular slide valve extends down below the lower open end of the cylinder and is pivotally attached to the operating mechanism, which in Figs. l and 2 comprises a lever 8 pivoted to said valve at a point between its ends, said ends being respectively pivoted to rods 9 and 10 adapted to be actuated by eccentrics 11 and 12. The eccentric 11 is arranged to rotate at the same speed as the main shaft which carries the crank pin 13, while the other eccentric 1-2 rotates at half that speed. l

The eccentrics impart to the tubular slide valve an up and down reciprocating movement by means of which` the slots in the valve and the cylinder vwall are caused to reglster in proper order and at the proper times and for the proper duration. For instance, the higher slot 4 controls the admiss1on of the mixture and the lower slot 5 the escape of the exhaust gases. Assuming that in Fig. l the engine .is at the beginning of a power stroke, both ports 4 and 5 are, out of line with the ports 6 and .7. vWhen the next upstroke begins, the tubular slide valve must have moved up till,the exhaust slot 5 regise ters with the exhaust port 7. At the conclusionv of this stroke, the valve must move downwardly till the admission slot 4 registers with the admission port 6 to permit the piston to suck in a fresh charge; At the end of said stroke the valve must resume the position in which it appears in the drawing and must remain there during the upward compression stroke and the succeeding downward power stroke of the piston. It need not remain entirely stationary during this "time, provided it does not move far enough to uncover either of the ports.

From the diagram, Fig. 6, may be seenthe different phases of the movement of the valve. The upper and lower dead centers of the crank are indicated by the numerals 14 and 15, respectively. The irregular line `curve produced by a single eccentric is symmetrical. It isi for this reason that I have devised the system shown and described, in which, two eccentrics are used, one rotating at a fraction of the speed of the other, and both acting upon a lever or other .element from which the tubular slide valve derives its movement. The preferred ratio is that of l 'to 2; that is to say, oneeccentric rotates at one half the speed of the engine shaft and the other at the. same speed thereof. By inspection of Fig. 7 the mode in which these two speeds over-lap is clear,l l

`Curve 19 is that produced by the faster- 23 and 24 parallel with the 4line 25.repre senting the middle point of the valve movement. These lines 23 and 24 indicate how far the valve must depart from its middle lposition before the opening` of the slot 4 or 5 occurs. Between these two lines the valve may make any movement necessary without bringing either of the slots into line with its respective port 6 or 7 Fig. 8 shows that there is some slight oscillation of the valve during the time that the slots remain closed; but this is immaterial.- Upon comparing Fig. 8 with Fig. 6,' it will be apparent that the movement given to the valve is very close to the movement required for a correct regulation thereof.

The two eccentrics may be mounted in various ways, Fig. 1 shows each eccentric on its own shaft; Fig. 2 shows the fasterrunning eccentric fixed directly on the engine shaft. Figs. 3,4 and 5 show arrangements in which one of the eccentric rods is used as a lever and is set in oscillating movement about its eccentric by the other eccentric. The lever may be a single-arm, a double-arm or a bell-crank in order to keep the exhaust open long enough and thus avoid an improper re-opening during the compression stroke, the eccentricities of the eccentrics and the lever-arm conditions may be such that the stroke of the tubular slide valve caused by the slower-running eccentric alone isv somewhat greater than that which is produced by the quicker-running eccentric alone. It is of further advantage, in order to obtain the opening of the admission port as early as possible, to have the mutual position vof the eccentrics such that the slow-running eccentric, in the movement which shuts off the exhaust, will not have reached the middle point between the two dead centers when the quicker-running eef'- centric, in the movement of like direction, is exactly ninety degrees from' the dead centers. By having suitably short eccentric rods, by limiting the crank drive of the tubular valve gear, by making the length' of the rod such that it is oblique to the proper lever-arm in its middle position, by

' elbow-lever action, and similar-means,'still further advantages may be secured. Instead of taking the quicker-running movement from a special regulating shaft or from an eccentric seated on the crank shaft, it is possible to take it from a suitable point on the connecting-rod. This partial movement is, it is true, not exactly symmetrical, on account of its being derived in an obllque direction and on account of the limited length of the connecting-rod, but it is nearly symmetrical, and by its character comes under the approximately symmetrical movements which are mentioned above and which are obtainable by means of eccentrics or, the like. The partial movement which is made more quickly may be produced by means of a swinging member which is set in energetic swinging movement by an eccentric rotating with half the number of revolutions of the motor( and the eccentricity of which is only a little smaller than the radius of the swinging member. In this way the rod which sets the swingingmember in movement will twice increase and twice diminish, during each rotation of the eccentric, its distance from the Ypoint of rotation of the swinging member. The swinging member may be used either as a lever or as a guide or in other suitable manner. For the purpose of combining the two symmetrical movements, the 'movement of the valve in the latter instance may be derived from a point which is fast connected with the eccentric rod.

In accordance with the provisions of the patent statutes, I have described the principle of operation of my invention, together with the apparat-us which I now consider to represent the best embodiment thereof; but I desire to have it understood that the appa- 'ratus shown is only illustrative and that the invention can be carried out by other means.

What I claim as new and desire to secure by Letters Patent of the United States, is

1. In an internal combustion engine, the combination of a cylinder having admission and exhaust ports through its wall adjacent the head of the cylinder, a piston, a tubular slide valve arranged between the piston and 'the cylinder wall and controlling said ports,

and means for moving said valve comprising a shaft which rotates at engine speed, a halfspeed shaft, eccentrics on said shafts, and a lever connected to said valve and operated by said eccentrics.

2. In an internal combustion engine, the combination of a cylinder .having admission and exhaust ports through its wall, a piston, a ,tubular slide valve arranged between the piston and the cylinder wall and controlling. said ports, and means for moving said valve comprising a shaft which rotates at engine speed, a half-speed shaft, eccentrics on said shafts, and' a'. lever havingits two ends connected to said eccentrics and operatively connected at an intermediate point to the va ve.`

3. In an internal combustion engine, the and means connecting said eccentrics with combination of a cylinder having admission the valve,v said means comprising a lever and exhaust ports through its wall adjacent attached. at one point to the valve and. at the head of the cylinder, said ports lying two other points to the eccentrics.

in substantially the same cross-sectional In witness whereof, l have hereunto set 15 plane, a piston, a tubular slide valve army hand this 22nd day of December, 1910.

ranged` between the piston and 'the cylinder RUDLPH URTEL. wall controlling said ports, and means for lylitnesses: moving said valve comprising two eccentrics, CONRAD BEL,

l@ one rotating at twice the speed of the other, JULIUS RUMLAND. 

